The historic Sandwich glass was not made in today's museum location but glass is produced at the museum currently.
Most of the pieces are produced on site at the museum.
The museum is in the center of town and the original factories were multiple buildings that took up a fair amount of the town as the company grew. Those buildings were destroyed after the company shut down.
Most are antiques, some yes some no. Gift store pieces and more modern pieces elsewhere.
Yes, most of them are made there and you can watch glassblowing.
A small portion of it was made in-house, but older glass pieces and some gifts are made in other places, even in different towns and states.
From what i can remember from my visit its a mix of both but mainly centred on the locally produced glass as there are live demonstrations of glass making / blowing.
Other locations. But there are glass blowing demonstrations at the museum.
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